22 Comments to "Tips/Tricks – How to control MaxLength of Multiline TextBox in ASP.NET 1.1?"

1. Christian López Espínola wrote:

   Don’t forget: Javascript can be disabled, so validate the user input always on the server side! :)

   Link | April 5th, 2007 at 10:34 pm

2. a n n i e wrote:

   wow
   you’re so smart
   i don’t know all of this stuff >O

   Link | April 6th, 2007 at 12:53 am

3. Michael Sync wrote:

   >>Don’t forget: Javascript can be disabled, so validate the user input always on the server side!

   ya.. good point.. thanks. man..

   Link | April 6th, 2007 at 3:03 am

4. Ashish wrote:

   added your link on my blog, add mine plz and also leave message if possible

   http://best-tweaks.blogspot.com

   thnx

   Link | April 6th, 2007 at 12:40 pm

5. Avenger069 wrote:

   I wouldn’t say that “Obviously, this is a bug of ASP.NET”. Actually I believe this is being handled properly by ASP.NET.

   MultiLIne texboxes are rendered as a TEXTAREA to the client. There is no maxlength property on a TEXTAREA. See the spec here: http://www.w3.org/TR/html4/interact/forms.html#h-17.7

   The single line textboxes are rendered as an INPUT element which does have a maxlength property. See here: http://www.w3.org/TR/html4/interact/forms.html#h-17.4

   So what’s really happening when you change the TexMode property of the asp:textbox control is you are changing what gets rendered to the client. While I think the proper result is taking place I believe that MS should make it a little more obvious what is happening by maybe blanking out the maxlength property when multiline is selected.

   Link | April 12th, 2007 at 5:48 pm

6. Andrew wrote:

   Good, but how about Cut & Paste?

   Link | April 17th, 2007 at 6:34 am

7. Michael Sync wrote:

   Hi Avenger069,

   Thanks for your comment and links. Avenger069
   Yeah. MS should do something about it. If they are not able to disable MaxLength property of ASP.NET TextBox then they should create the seperated controls for single textbox and textarea..

   Hi Andrew,
   >>how about Cut & Paste?
   Let me check about this.. I will reply you asap..
   Thanks.

   Link | April 18th, 2007 at 3:11 am

8. Amit wrote:

   Hi,

   instead of return false.
   use
   event.returnValue = false;
   works better

   Link | May 22nd, 2007 at 11:10 am

9. Michael Sync wrote:

   thanks. I’ll try to test it.
   Thanks again. Amit.

   Link | May 22nd, 2007 at 1:56 pm

10. shobhit wrote:

    thans for the wonderfull article.
    but this function wont work when cut & paste..
    plz help…………

    Link | June 12th, 2007 at 5:32 am

11. Michael Sync wrote:

    what errs are you getting??

    Link | June 12th, 2007 at 6:59 am

12. Leo wrote:

    I had the problem that i could no more delete text if max len was reached. Also i saw that this script works not if i paste some text longer then the max into this textfield..

    So i changed the function as follows:

    function checkMaxLen(txt,maxLen) {
    try{
    if(txt.value.length > (maxLen-1)) {
    var cont = txt.value;
    txt.value = cont.substring(0,(maxLen -1));
    return false;
    };
    }catch(e){
    }
    }”;

    and i use the onkeyup instead of the onkeypressed – Event….

    Link | July 12th, 2007 at 4:29 pm

13. JDS wrote:

    I want to point out another problem with the first solution. Once you actually reach the max length, the textarea won’t accept any more input. Trouble is this includes backspace, delete and arrow buttons.

    Link | September 13th, 2007 at 12:37 pm

14. Nisha wrote:

    Thanks! it works. i stuck with this point. thanks again.

    Link | October 9th, 2007 at 1:12 pm

15. johny why wrote:

    i don’t quite agree with Avenger069 that it’s being handled properly by asp.net. it may be correct to say that a textarea does not have a maxlength property, but as asp.net developer, i care not whether microsoft renders my asp:textbox as an input, a textarea, or a banana, as long as it behaves properly. that’s the whole point of asp.net– the programmer does not (ideally) need to be concerned with how the server controls are rendered– asp.net is supposed to generate browser-specific client-side script. maxlength is an essential and obvious property, which should be available for both single-line and multiline textboxes.

    Link | May 9th, 2008 at 6:59 am

16. sathian wrote:

    hi michael,

    I was searching for this script past 2 days in many site, now I got this script in your site, this is very helpful my project. That’s great. Thanks again.

    Regards,

    Sathian. K

    Link | August 20th, 2008 at 12:22 pm

17. Nimish Rao wrote:

    hi,
    using the try catch block in JavaScript is useful?That is i can get the exception?thereby helping me in the impossible task of debugging JavaScript for ASP2.0?

    Link | January 6th, 2009 at 9:52 am

18. almnynet wrote:

    thanks man
    i shearch about it
    and your code working good :)

    Link | April 18th, 2009 at 11:48 pm

19. lamle wrote:

    Thanks for your information.

    Link | June 19th, 2009 at 3:02 am

20. sgl wrote:

    good job mate. perfect.

    Link | July 22nd, 2009 at 7:34 am

21. Kurt wrote:

    Michael, very cool. I couldn’t use the regex solutions that are often suggested with the RegEx Validator Controls due to some strange postback business on my page. Leo makes the solution complete by adding cut&paste capability. I would suggest melding the two to one solution. One caveat: I don’t get taking maxlength-1. If the max length is 10 characters, then I want 10 characters max not 9.

    Link | October 26th, 2009 at 11:41 am

22. Gregor suttie wrote:

    Unfortunate that I can paste in as much text as I want – which makes the necessity for server side validation very real.

    Link | March 30th, 2010 at 5:19 am

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